Process for coloring etchings on glassware



Oct. 1, 1935. 4N. H. MAGEE ET AL PROCESS FOR COLORING ETCHINGS ON GLASSWARE l Filed Dec. 22, 1951 EWIIIIII Patented er. 1, 1935 UNITED STATES PROCESS FOR COLORING ETCHINGS 0N GLASSWARE Norman H. Magee and John A. Patterson, Jr.,

Philadelphia, Pa., assignors to John M. Maris Company, Inc., a corporation of Pennsylvania Application December 22, 1931, sei-iai No. 582,647

4 Claims.

Our invention relates to new and useful improvements in the art of producing colored 'etchings on glassware.

Ordinarily, when it is desired to color etchings upon glassware, which etchings have been produced either by grinding or by the use of hy- .drofluoric acid, some colored opaque-material,

such as enamel is used to ll in the ground-in or chemically etched markings on the glass surface, to make the samevisible. Such coloring materials, used to ll in the said markings, lack permanency, and are worn oil in ordinary use, during washing or handling or in the event of contact with some corrosive chemicals.

It is our object to provide a chemical process for coloring etchings upon glassware, which will eliminate much labor in coloring of the markings,

and at the same time, produce a form of coloring l appropriate precipitating agents, which leaves the precipitate lodged within the etched markings as an insoluble metallic inorganic compound or compounds, or mixtures. This is followed by rinsing in water and removing the vprotective coating, then by dehydrating the lodged precipitates, to cause a greater adherence of the same to the glass. We select such metallic salt or salts and appropriate precipitating agent or agents as will give us the desired color or shade of color.

The inorganic metallic compounds adapted for the purposes of our process, may be listed as oxides or hydroxides, silicates, chromates, sulphates, carbonates, including also barium sulfate, ferrous ferricyanide, fern'c ferrocyanide,

-silver arsenate, silver arsenite, silver chloride, silprocess. Opposite each compound, we have given the corresponding color of the resulting precipitate formed, as follows:

The arides or hydroxides Chrnmir' Green y Lead (lltharge, PbO) Yellow or red Magnesium.. White Tin (stannic, SnOz) White 1 The carbonates Cobaltus Red Barium AWhite ycorresponding to the design or lettering, for sub- The suldes Copper Black Iron Black Mercury Black or red Antimony (SbzSa) Black or brown 5 Antimony (SbzSs) Orange Arsenic (AszSz) Red Arsenic (AszSa) .y Yellow Arsenic (AszSs) Yellow Cadmium YellOW 10 l Nickel Black Lead -Black or brown The chromates Lead Yellow Silver /Red Mercury Red And in addition, Barium sulfate White Ferrous ferricyanide Light blue Ferric ferrocyanide Dark blue Silver arsenate Red Silver arsenite Yellow Silver chloride White Silver bromide Yellow Silver iodide Yellow Lead basic carbonate White Also the silicates of Aluminum, bismuth, boron, cadmium, calcium, chromium, cobalt, copper,

iron, lead, magnesium, manganese, mercury,

nickel, silver, tin, titanium, and zinc, may be used.

More specically, let us assume it is desired to produce yellow markings on glassware, then our process for producing a yellow coloring of hydroiluoric acid etched markings may be stated as follows:

The glassware is first coated all over with some 40 protective coating, as wax, to protect the parts of the glass surface which are not exposed for the etched markings, when the glass piece is immersed in any of the various chemical baths used in our process.y After the design or lettering to be marked upon the glass, is either ground thereon, through the protective coating or the lines of the design or lettering cut through the said coating, merely to expose the glasssurace in lines sequent etching by the usual bath of hydrofluoric acid, solution, then the glass article, so marked through its solution coating, is given avvbath of -hydrofluoric acid solution and is left long enough immersed to lodge certain uorides along' the 5 5 lines of the markings, which have been either ground in through the coating, or where the glass usual way -of forming the markings for subsequent etchings by the use of a hydroiiuoric acid solution, the glassware is immersed inY a hydrouoric acid solution to form the etchings in the lines of the markings and is next rinsed in cold water, 's0 as not to disturb the protective coating, yet leave some fluorides lodged in the etchings, and after so rinsing the glass article, it is given a second treatment by immersing again in a hydrouoric acid frosting solution containing ammonium salts to form an etched frosting along the markings. In the case where the markings are ground into the glass through the protective coating this first bath of hydroiiuoric acid solution is omitted, but the subsequent treatment is the same, whether the markings were formed by .grinding in, or were formed by the use of a stylus and etched in by hydrouoric acid Before proceeding further, the glassware is rinsed. Then follows, in either case, the next step which consists in immersing the glassware in a solution of lead acetate, containing a slight excess of acetic acid. The glassware is held long enough in this last mentioned solution to dissolve the i'luorides remaining upon the etched lines of the glass and to wet these lines in thev glass with the lead salts formed. The glassware is next rinsed in cold water and subsequently immersed in a solution of ammonium bichromate, forming insoluble lead chromate, as a precipitate, lodged within the said etched markings. After being in this last bath long enough to attain the desired results, ascertained by practice, the glassware is allowed to dry off in the air long enough to dehydrate the precipitate causing it to adhere more firmly to the glass, after which the glassware is washed off in boiling hot water or other suitable liquid to remove the protective coating, and then the glassware is in a finished condition to bewiped dry, leaving yellow markings practically, permanently fixed upon the glassware.

In a similar way, the chemist who is familiar with this art will readily understand how to get any other desired color by using the suggestions above tabulated in selecting the proper metallic salt and its corresponding precipitant for the color desired, as he carries out a like sequence of steps, as above described for producing the yellow markings on the glassware.

In order to graphically portray the various steps taken, as well as to indicate the nature of the chemical baths, through which the glass article is passed, to produce the anchored colored precipitates, at the etchings, we have shown in Figure 1, a perspective view of a glass platel I0, covering with a protective coating II, through which a broad marking I2 has been scratched, to expose the glass surface at I3. In Figure 2, the dish I4 is shown in section, to hold the glass plate I0, in a bath I5 of solution containing hydrofluoric acid as the usual etching bath, to form the initial etching, where I6 represents the layer of fluorides, constituting this etching.

In Figure 3 the dish I4 is shown in section, to hold the glass plate Il), in a different bath I1, or one of solution of hydroiluoric acid mixed with ammonium salts, thereby producing the microscopic pits indicated at I8, in this Figure 3, the modified etching layer being indicated at I9. In Figure 4, the dish I4 is shown in section to hold the glass plate I0 in a bath 20, containing a metallic salt, which chemically combines with the uorides formed in the previous baths,v the changed etching being here marked 2l.

Figure 5 shows the dish I4 in section holding the plate Il), in a bath 22, of solution containing an appropriate reagent to .the metallic salt used in bath 20, thel further changed and colored etching being marked 23. Figure 6 is a perspective view of the nished plate I0, with a colored and anchored etching 23, having the protective coating II removed.

Inasmuch as modifications of our process of forming colored etchings on glassware can be used without departing from the spirit and scope of our invention, we wish to include all which come within the purview of the following claims.

We claim:

1. The process of chemically treating a glass surface to produce anchored colored etchings thereon, which includes the following steps;

first, covering the surface of the glass with some protective coating, as a suitable wax, then making markings of the desired design or letteringv thru the said coating to expose the surface of the glass to be etched, then immersing the glass in a bath of solution containing hydroiluoric acid, as the usual etching bath, to form the initial etching at the said markings, next following this initial etching with the production of a chemical and physical anchorage for the subsequently produced colored precipitates by means of giving the glass a bath of solution of hydroiluoric acid mixed with ammonium salts, whereby producing a pitted surface at the said markings, together with added uorides, following this pitting of the glass surface with a bath containing metallic salt, and subsequently immersing the said glass in a bath containing an appropriate reagent to the metallic salt used, whereby the colored precipitate so produced, reaches down into the said pitted surface to be more rmly secured against wear.

2. The process of chemically treating a glass surface to produce anchored colored etchings thereon, which includes the following steps: rst, covering the surface of the glass with some protective coating, as a suitable wax, then making markings of the desired design or lettering throughthe said coating to expose the surface of ,the glass to be etched, then immersing the glass in a bath of solution containing hydrouoric acid, as the usual etching bath, to form the initial etching at the said markings, next following this initial etching with the production of a chemical and physical anchorage for the subsequently produced colored precipitates by means of giving the glass a bath of solution of hydrofluoric acid mixed with ammonium salts, whereby producing a pitted surface at the said markings together with added fluorides, following this pitting of the glass surface with a bath containing metallic oxide, 'and subsequently immersing the said glass in a bath containing an appropriate reagent to the metallic oxide used, whereby the colored precipitate so produced, reaches down into the said pitted surface to be more rmly secured against wear.

3. The process of chemically treating a glass surface to produce anchored colored etchings thereon, which includes the following steps: First, covering the surface of the glass with some protective coating, as a suitable wax, then making markings of the desired design or lettering through the said coating to expose the surface of the glass to be etched, then immersing the glass in a bath of solution containing hydrofluoric acid, as the usual etching bath, to form the initial etching at the said markings, next'following this initial etching with the production of a chemical and physical anchorage for the subsequently produced colored precipitates by means of giving the glass a.l bathof solution of hydrouoric acid mixed with ammonium salts, whereby producing a pitted surface at the said markings, together with added iluorides, following this pitting of the glass surface with a bath containing metallic carbonate, and subsequently immersing the said glass in a bath containing an appropriate reagent to the metallic carbonate used, whereby the colored precipitate so produced, reaches down into the said pitted surface to be more rmly secured against wear.

4. The process of chemically treating a glass surface to produce anchored colored etchings thereon, which includes the following steps: first, covering the surface of the glass with some protective coating, as a suitable wax, then making markings of the desired design or lettering through the said coating to expose the surface of the glass to be etched, then immersing the glass in a bath of solution containing hydroiluoric acid, as the usual etching bath, to form the initial etching at the said markings, next following this initial etching with the production of a chemical and physical anchorage for the subsequently produced colored precipitates by means of giving the glass a bath of solution of hydroiuoric acid mixed with ammonium salts, whereby producing a pitted surface at the said markings, together with added iluorides, following this pitting of the glass surface with a bath containing metallic silicate,

and subsequently immersing the said glass in a bath containing an appropriate reagent to the metallic silicate used, whereby the colored precipitate so produced, reaches down into the said pitted surface to be more firmly secured against Wear.

NORMAN H. MAGEE. JOHN A. PATTERSON, JR. 

